POLYIMIDE FILM, METHOD FOR PRODUCING POLYIMIDE FILM, AND POLYIMIDE PRECURSOR RESIN COMPOSITION

A resin film has improved rigidity and flex resistance, and reduced optical distortion. A polyimide film has a polyimide containing an aromatic ring, and inorganic particles having a smaller refractive index in a major axis direction than an average refractive index in a direction perpendicular to the major axis direction, wherein, when the polyimide film is monotonically heated from 25° C. at 10° C./min, a size shrinkage ratio represented by the following formula in at least one direction is 0.1% or more at at least one temperature in a range of from 250° C. to 400° C.: size shrinkage ratio (%)=[{(size at 25° C.)−(size after heating)}/(size at 25° C.)]×100; wherein a birefringence index in a thickness direction is 0.020 or less at a wavelength of 590 nm; and wherein a total light transmittance measured in accordance with JIS K7361-1 is 80% or more at a thickness of 10 μm.